1. Technical Field
The present invention relates to image processing apparatuses, and particularly relates to an image processing apparatus, connected to an ejection head in which a nozzle group configured of nozzles that eject CMY inks of the CMYK color system and a nozzle group configured of nozzles that eject K ink of the CMYK color system are formed at different nozzle densities, that converts inputted image data into print data and outputs the print data to the ejection head.
2. Related Art
As a past example of such an image processing apparatus, an apparatus including a shared memory provided with two buffer regions, a main data processing unit that interprets document data such as XHTML, generates raster data in which tone values are recorded on a pixel-by-pixel basis, and writes the raster data into a buffer region of the shared memory, and a sub data processing unit that generates print data by performing a halftone process and the like on the raster data written into the buffer region, has been proposed (for example, see JP-A-2004-98636). The disclosure proposes that with such an apparatus, the throughput of the apparatus as a whole can be improved by the sub data processing unit processing raster data written into one of the buffer regions and, during this period, the main data processing unit writing the raster data for the next print into the other buffer region.
With such data processing units, various data processes can normally be carried out by accessing an individual memory within that data processing unit itself; however, in the case of a configuration in which multiple data processing units can access a shared memory as described above, it is necessary to prevent the data processing units from accessing the same buffer region at the same time. For this reason, it is necessary to provide each of the data processing units with new functionality for limiting free access to the shared memory, which complicates the configuration of the apparatus, increases costs, and so on.